The first stage to planning a compressed air pipe system is working out the flow rates.
This is achieved by looking at the flow rate of your compressor or the flow required by the equipment using air. We have included tables for compressor flow rates and typical tool air usage.
The following is a guideline to work out the output of your compressor:
| Power of compressor motor (KW) | Approximate flow rate (cfm) |
| 1.5 | 8 |
| 4 | 23 |
| 5.5 | 32 |
| 7.5 | 42 |
| 11 | 62 |
| 15 | 88 |
| 22 | 124 |
| 55 | 300 |
| 110 | 636 |
Typical air tool flow rates
| Tool | Flow rate required approx. (cfm) |
| Tyre Inflator | 1.5 |
| DA Orbital Sander | 15 |
| HVLP Spraygun | 20 |
| Air Drill | 5 |
| Blow Gun | 4 |
| 1/2″ Impact Wrench | 4 |
| 1″ Impact Wrench | 12 |
Once you have a figure to work with compare it to our table below to work out the size of pipe you require. The column on the left shows the cfm flow rating and the row on top shows the distance from the compressor to the furthest outlet in metres. Follow the lines down and across to highlight the tube size you require.
| 25m | 50m | 100m | 200m | 500m | 1000m | |
| 8 cfm | 20 | 20 | 20 | 20 | 20 | 20 |
| 23 cfm | 20 | 20 | 20 | 25 | 25 | 32 |
| 32 cfm | 20 | 20 | 20 | 25 | 32 | 32 |
| 42 cfm | 20 | 20 | 25 | 25 | 32 | 40 |
| 62 cfm | 20 | 25 | 25 | 32 | 40 | 40 |
| 88 cfm | 25 | 25 | 32 | 32 | 40 | 50 |
| 124 cfm | 25 | 32 | 32 | 40 | 50 | 50 |
| 300 cfm | 40 | 40 | 50 | 50 | 63 | 63* |
| 636 cfm | 50 | 50 | 63 | 63 | 110 | 110 |
| 1766 cfm | 63 | 110 | 110 | 110 | 110* | 110* |
| 3531 cfm | 110 | 110 | 110 | 110* | 110* | 110* |
Measurements calculated at 7 bar – * Pressure drop is higher than 4%
Further considerations include:
What will it be clipped to or hung from? Ceiling, wall. What will be on the outlet? Regulator, gauge, quick release coupling. Where should isolation valves be placed? Will there be expansion in the future?
